In unlicensed mobile access (UMA) networks or generic access networks (GANs) a client needs to communicate with multiple functions on nodes to register on the network. This involves creating and tearing down multiple IPSec tunnels with the nodes. For example, a client first communicates with a security gateway where it is authenticated, which involves bringing up a first IPSec tunnel with a security gateway. After authentication, a registration request is sent to a provisioning GAN controller (P-GANC) to retrieve information on which default GAN controller (D-GANC) to contact. To connect to the D-GANC, the IPSec tunnel is terminated with the security gateway connected to the P-GANC and a new IPSec tunnel is established to a security gateway co-located with the D-GANC. Finally, the D-GANC communicates the location of a serving GANC (S-GANC). The client tears down the IPSec tunnel with the security gateway co-located with the D-GANC and then establishes a new IPSec tunnel to the security gateway co-located with the S-GANC in establishing a session.
Accordingly, multiple IPSec tunnels are brought up and torn down in the registration process. This involves a lot of processing power and is expensive. Further, the cost of maintaining the different nodes, such as the P-GANC, is costly especially when their functions in the call flows are limited.